apomixis and dichotima

Jan Schlauer (zxmsl01@student.uni-tuebingen.de)
Wed, 15 Mar 1995 10:02:29 +0100

Terry and others who might be interested,

>VFT's are known for producing new plantlets from flower spikes
>while they are still attached to the plant (Is apomixis the
>correct term?).

Apomixis is a term for seed set with the embryo originating directly from a
vegetative cell and not from a zygote (i.e. without fertilization,
frequently observed e.g. in _Taraxacum_). If even the "seed step" is
omitted and new plants are formed directly, it is called vegetative
apomixis.

>What is a D. dichotima (sic)?

dichotima is a sphalma typographicum (but as its derivation is too obvious,
and as long as it will not influence scientific literature, I will not list
it in my synopsis) of dichotoma.

> I take it you are referring to a
>_D. binata_ "dichotoma" (have I got the right quote marks here?).

Well, D.binata var.dichotoma (BANKS & SOLAND. ex SM.) MAZRIMAS is a
combination of rather disputable status. It was obviously intended to be
based on D.dichotoma BANKS & SOLAND. ex SM., but the basionym was not cited
in the publication (CPN 5:15, 1976), ergo nomen illegitimum (with the ICBN
applied strictly). I am not so rigorous in my synopsis with infraspecific
taxa and hybrids from the horticultural trade. Otherwise, many more names
would have to be disqualified as illegitimate, and as they are marked as
synonyms anyway, it does hopefully not do too much harm; they must in any
event be considered as possible homonyms (cf. N. *rubromaculata HORT.
VEITCH ex WILSON vs N.rubromaculata auct. non HORT. VEITCH ex WILSON:
KURATA! In this case, the first name is not even illegitimate, however).

Because var.dichotoma was published *like* a taxonomic variety (i.e. not as
a cultivar: cultivars cannot be based on scientific epithets!), you should
not use any quote marks (single quotes are reserved for cvars.).

Anyway, as most authors (e.g. MARCHANT) consider the (several)
morphological and/or cytological variants (races?) of _Drosera binata_ to
be taxonomically irrelevant and/or interconnected by intermediates, it is
probably best to lump them all under _Drosera binata_ s.l.

Kind regards
Jan